204 



The Canadian Horticulturist. 



QUESTION DRAWER 



The Pithy Gall of the Blackberry. 



53. I ENCLOSE to you by to-day's mail a pecu- 

 liar growth found on a Brinckle's Orange rasp- 

 l9erry cane in the garden of Mr. J. H.Davison, of 

 this'town. Mr. Davison showed it tome some 

 days ago, when I suggested that it be sent 

 to you for examination and description in 

 the Horticulturist. The cane upon which it 

 was found was dead and when the knot was 

 cut open there was found in it a small black 

 fly about a sixteenth of an inch in length. 

 Please give us your opinion. — W. A. Brown- 

 lee, Mt. Forest. 



This peculiar growth is a gall 

 caused by a gall-fly belonging to the 

 family Cyripida:, and known to our 

 entomological friends as Diastrophus 

 Ncbulosus. The tumor is formed by 

 the unnatural growth of the vegetable 

 cells, which is produced by the 

 depositing of the eggs. The tumor 

 or gall is soft and spongy, and the 

 one sent us is shown in the engrav- 



Fig- 53- 



ing, Jig. 53 « , with little holes, through 

 which the flies have escaped. The 

 section b shows the interior, with 

 several oblong cells, about an eighth 

 of an inch in length, each of which 

 has contained a larvae, or yoimg 

 grub, one of which is more plainly 

 shown at c. These are about one- 

 tenth of an inch long, white, with 

 reddish mouth ; they remain through 



the winter safely hidden in these 

 galls, and change to flies in the 

 spring-time. The fly is described as 

 black, with transparent wings and 

 red feet and antennae. They more 

 commonly attack the blackberry 

 canes than the raspberry, but are not 

 very troublesome, as thej^ are destroy- 

 ed by parasitic insects and by birds. 



Kerosene for Bark-Lice. 



54. Sir,— A friend of mine in Toronto gives 

 the following method of dealing with the 

 Oyster Shell Bark Louse nuisance: — 



" In early spring, before the buds commence 

 to swell, apply crude petroleum to the affected 

 parts." 



He assures me that no injury whatever is 

 done tlie trees by this treatment, and that when 

 growth commences in the spring, the outer 

 bark of all twigs so treated will peel off, taking 

 with it all the shells with its eggs, and leaves 

 the inner bark smooth as if polished. 



Will you please give your readers your 

 opinion of this — to me — new treatment. — Thos. 

 Beall, Lindsay. 



We have tried this remedy and 

 find it certainly most effective in' 

 destroying the bark lice. Not a 

 single one remained to tell the story 

 of the disaster. But the bark of the 

 tree in places was totall}' destroyed 

 also. On one tree three applications 

 were made, washing the bark thor- 

 oughly with a cloth dipped in the 

 oil ; on another only one application 

 was made. On the former the bark 

 was so badly killed that the tree 

 must eventually die ; on the latter it 

 was only killed in places on the under 

 side of the limbs, where it would 

 naturally collect. 



The only safe mode of applying 

 kerosene is as an emulsion with soap 

 and water. A half pound of soap, 

 dissolved in a few quarts of water, 

 is set on the stove until it boils. 

 Then while boiling add two gallons 

 of kerosene, stirring at the same 

 time, and a perfect emulsion will be 

 formed. This may be applied with 

 an old broom, or a scrubbing brush, 

 after first scraping ofl" the loose bark, 



